Electric motors are often used to drive mixers or pumps in pharmaceutical, chemical, and food processing applications. Such electric motors are routinely exposed to debris which can accumulate within the motor and, if not properly cleaned, can lead to undesirable results such as cross-contamination, dirt accumulation, and/or bacterial growth. As a result, electric motors used at food processing, pharmaceutical, and biotech facilities can be subjected to frequent sanitation-required wash downs in order to remove undesired residue from product debris, cleaning reagents, soils, and the like.
A typical electric motor can have a housing including a cylindrical casing and a pair of end caps. The motor can include a rotor attached to a shaft and a stator surrounding the rotor. One end of the shaft can extend through one of the end caps for attachment to operating equipment, such as a mixer or pump. An opposite end of the shaft can extend through the other of the end caps and can have a fan attached thereto for purposes of providing circulation for cooling the motor. A fan shroud may be attached to the other of the end caps for covering the fan.
Electric motors as described above can include complex geometries that can render the motors difficult to wash and clean. Partial disassembly, such as removal of the fan shroud, can be necessary in order to access the fan for cleaning. Even after removal of the shroud, the electric motor can be difficult to clean. For example, fan shrouds mounted on the casing using sheet metal brackets or localized deformation in combination with machine screws can result in significant crevices that can accumulate and retain undesired residues. Similarly, cooling fans, which are frequently made of plastic and have numerous pockets or crevices as part of their design and are secured to a knurled shaft surface, result in crevices and surfaces that can be difficult to properly clean and provide multiple surfaces for undesired particles to accumulate. In some instances, the complex exterior geometries of the electric motors can result in hard-to-reach areas, such as within a fan shroud, where debris can be difficult to remove, a particular disadvantage in applications in the food, biotech, and pharmaceutical industries.